Impingement food ovens are mostly used in fast food restaurants for rapidly cooking food such as pizza, pre-cooked meals, sea food souffle, cookies, etc. by air streams which impinge against the surface of the food products. Example of prior art impingement food oven are described by way of example in U.S. Pat. No. 5,584,237 in the name of the applicant; U.S. Pat. Nos. 5,584,237; 5,423,248; 4,965,435; 4,462,383; and 4,753,215.
There is also the reference EP-0286759, which discloses a convection oven comprising a plurality of finger ducts mounted in parallel in the baking chamber of the oven. Each of the finger ducts has an air inlet to receive heated air from a plenum and a plurality of air outlets to dispense the heating air in the baking chamber.
Most of prior art impingement food oven comprises finger ducts mounted in the cabinet of the oven above and below a conveyor to form streams of forced heated air which are directed towards the product on a conveyor. In general, the finger ducts rapidly become dirty or fouled up and must be regularly cleaned up. In prior art, the finger ducts are independent from each other so that they are mounted or dismounted one by one by sliding each one of those in guide rails adapted to receive a corresponding finger duct. As can be easily understood, the cleaning up of all the finger ducts is time-consuming and very expensive because each of those finger ducts has to be removed, cleaned up and put back in the oven, one after another. Moreover, often, the finger ducts are not put back in their proper place, causing an improper cooking of the products. There is thus presently a need for an impingement convection oven provided with finger ducts that may be rapidly and easily dismounted from the oven or installed therein.
Another drawback often encountered with the elongated finger ducts of prior art impingement food ovens is that the heated air leaving the plenum and forced in each finger duct is moved directly to the opposite end of the finger duct due to its high velocity and causes the food to be cooked uneven. Attempts to resolve this problem by using deflectors mounted inside the finger duct in order to apportion the incoming air flow therein have been proposed in U.S. Pat. Nos. 4,462,383 and 5,423,248. However the design of the deflectors proposed in those prior art documents have not shown satisfactory results and often does not provide a uniform cooking between the product on the front portion of the conveyor and the one in the back portion. There is thus also a need for an impingement convection oven that will consistently show a uniform cooking throughout the oven.